There is a new associative learning paradox. The power of associative learning for producing flexible behaviour in non-human animals is downplayed or ignored by researchers in animal cognition, whereas artificial intelligence research shows that associative learning models can beat humans in chess. One phenomenon in which associative learning often is ruled out as an explanation for animal behaviour is flexible planning. However, planning studies have been criticized and questions have been raised regarding both methodological validity and interpretations of results. Due to the power of associative learning and the uncertainty of what causes planning behaviour in non-human animals, I explored what associative learning can do for planning. A previously published sequence learning model which combines Pavlovian and instrumental conditioning was used to simulate two planning studies, namely Mulcahy & Call 2006 'Apes save tools for future use.' Science 312, 1038-1040 and Kabadayi & Osvath 2017 'Ravens parallel great apes in flexible planning for tool-use and bartering. 'Science 357, 202-204. Simulations show that behaviour matching current definitions of flexible planning can emerge through associative learning. Through conditioned reinforcement, the learning model gives rise to planning behaviour by learning that a behaviour towards a current stimulus will produce high value food at a later stage; it can make decisions about future states not within current sensory scope. The simulations tracked key patterns both between and within studies. It is concluded that one cannot rule out that these studies of flexible planning in apes and corvids can be completely accounted for by associative learning. Future empirical studies of flexible planning in non-human animals can benefit from theoretical developments within artificial intelligence and animal learning.

Social transmission of information is a key phenomenon in the evolution of behaviour and in the establishment of traditions and culture. The diversity of social learning phenomena has engendered a diverse terminology and numerous ideas about underlying learning mechanisms, at the same time that some researchers have called for a unitary analysis of social learning in terms of associative processes. Leveraging previous attempts and a recent computational formulation of associative learning, we analyse the following learning scenarios in some generality: learning responses to social stimuli, including learning to imitate; learning responses to non-social stimuli; learning sequences of actions; learning to avoid danger. We conceptualize social learning as situations in which stimuli that arise from other individuals have an important role in learning. This role is supported by genetic predispositions that either cause responses to social stimuli or enable social stimuli to reinforce specific responses. Simulations were performed using a new learning simulator program. The simulator is publicly available and can be used for further theoretical investigations and to guide empirical research of learning and behaviour. Our explorations show that, when guided by genetic predispositions, associative processes can give rise to a wide variety of social learning phenomena, such as stimulus and local enhancement, contextual imitation and simple production imitation, observational conditioning, and social and response facilitation. In addition, we clarify how associative mechanisms can result in transfer of information and behaviour from experienced to naive individuals.

Many questions in animal intelligence and cognition research are challenging. One challenge is to identify mechanisms underlying reasoning in experiments. Here, we provide a way to design such tests in non-human animals. We know from research in skill acquisition in humans that reasoning and thinking can take time because some problems are processed in multiple steps before a solution is reached (e.g., during mental arithmetics). If animals are able to learn through similar processes their decision making can be time consuming, and most importantly improve if more time to process information is allowed. We tested if performance of two Sumatran orangutans (Pongo abelii) increased in a two-choice experiment when they were allowed extra time before making their decisions, compared to when they were forced to decide immediately. We found that the performance of the orangutans did not depend on the time they were allowed to process the information before making their decisions. This methodology provides a potential avenue for empirical tests of mechanisms underlying reasoning in non-human animals.

In this paper, I draw on knowledge from several disciplines to explicate the potential evolutionary significance of health effects of religiosity. I present three main observations. First, traditional methods of religious healers seldom rely on active remedies, but instead focus on lifestyle changes or spiritual healing practices that best can be described as placebo methods. Second, actual health effects of religiosity are thus mainly traceable to effects from a regulated lifestyle, social support networks, or placebo effects. Third, there are clear parallels between religious healing practices and currently identified methods that induce placebo effects. Physiological mechanisms identified to lie behind placebo effects activate the body's own coping strategies and healing responses. In combination, lifestyle, social support networks, and placebo effects thus produce both actual and perceived health effects of religiosity. This may have played an important role in the evolution and diffusion of religion through two main pathways. First, any real positive health effects of religiosity would have provided a direct biological advantage. Second, any perceived health effects, both positive and negative, would further have provided a unique selling point for religiosity' per se. Actual and perceived health effects of religiosity may therefore have played an underestimated role during the evolution of religiosity through both biological and cultural pathways.

This book takes the reader on a journey, navigating the enigmatic aspects of cooperation; a journey that starts inside the body and continues via our thoughts to the human super-organism.

Cooperation is one of life’s fundamental principles. We are all made of parts – genes, cells, organs, neurons, but also of ideas, or ‘memes’. Our societies too are made of parts – us humans. Is all this cooperation fundamentally the same process?

From the smallest component parts of our bodies and minds to our complicated societies, everywhere cooperation is the organizing principle. Often this cooperation has emerged because the constituting parts have benefited from the interactions, but not seldom the cooperating units appear to lose on the interaction. How then to explain cooperation? How can we understand our intricate societies where we regularly provide small and large favors for people we are unrelated to, know, or even never expect to meet again? Where does the idea come from that it is right to risk one’s life for country, religion or freedom? The answers seem to reside in the two processes that have shaped humanity: biological and cultural evolution.

Primate Social Evolution2018In: The International Encyclopedia of Anthropology, John Wiley & Sons, 2018Chapter in book (Refereed)

Abstract [en]

Primates display a remarkable diversity of types of social organization—a diversity that, according to the socioecological model of social evolution, is ultimately determined by ecological factors limiting female fitness and the number of matings limiting male fitness. The foremost ecological determinants of female sociality are the degree to which food resources are defendable, either alone or in a group, and the level of protection from predators gained from being part of a group. Further factors that have been proposed are the presence of infanticide, coalitions, and dominance hierarchies; general population density and habitat saturation; whether competition is mainly intra‐ or intergroup; and which sex disperses. Male sociality is instead mainly determined by the spatiotemporal spacing of mating opportunities with females. Some researchers have also proposed that cognitive abilities impose a limit on group size, since primate sociality demands competent navigation of social networks.

Religion may affect personal health in at least two ways. First, religious prescriptions concerning matters such as diet, waste, sexual relationships and social support networks may have actual health consequences. Second, religious healing practices may induce placebo and nocebo responses. Through such mechanisms, religion can result in both positive and negative health effects, depending on prescriptions and rituals involved. Contingent on magnitude, health effects may constitute an underestimated component in understanding the prevalence and persistence of religions in human societies. Health aspects of religion may have become important in human societies through natural selection of susceptibility to placebo responses from religious healing rituals, or through cultural selection of components of religions that involve functioning health advice or that have piggy-backed on practices invoking placebo responses. What exact significance health effects have for understanding the persistence and ubiquity of religions remains to be thoroughly investigated, however.

This paper presents a new approach for studying temporal sequences across ordinal variables. It involves three complementary approaches (frequency tables, transitional graphs, and dependency tables), as well as an established adaptation based on Bayesian dynamical systems, inferring a general system of change. The frequency tables count pairs of values in two variables and transitional graphs depict changes, showing which variable tends to attain high values first. The dependency tables investigate which values of one variable are prerequisites for values in another, as a more direct test of causal hypotheses. We illustrate the proposed approaches by analyzing the V-Dem dataset, and show that changes in electoral democracy are preceded by changes in freedom of expression and access to alternative information.

This paper presents a new method inspired by evolutionary biology for analyzing longer sequences of requisites for the emergence of particular outcome variables across numerous combinations of ordinal variables in social science analysis. The approach involves repeated pairwise investigations of states in a set of variables and identifying what states in the variables that occur before states in all other variables. We illustrate the proposed method by analyzing a set of variables from version 6 of the V-Dem dataset (Coppedge et al. 2015a, b). With a large set of indicators measured over many years, the method makes it possible to explore long, complex sequences across many variables in quantitative datasets. This affords an opportunity, for example, to disentangle the sequential requisites of failing and successful sequences in democratization. For policy purposes this is instrumental: Which components of democracy are most exogenous and least endogenous and therefore the ideal targets for democracy promotion at different stages?

1. Jasso argued that her indirect method for inferring just rewards ispreferable to direct methods because the former is less susceptibleto biases. We pointed out that this claim was merely speculative andthat old and new evidence show both methods to be susceptible tosevere biases.

2. Results from our research found that the two methods were uncorre-lated over the identical set of stimuli, and hence at least one of themethods must be very unreliable. Of the two methods, only the indi-rect method inferred just rewards that were implausibly extreme, astrong indication that it is the less reliable. This was evident inresults that Jasso reported in 2008 but did not address at that time.

3. Direct and indirect methods both must assume that respondents havein mind just rewards for practically any set of contextual factors. This assumption is both unproven and implausible. The alternativeassumption is that respondents use contextual cues to help them ren-der fairness judgments but, as a consequence, their judgments arebiased by those cues.

4. We noted that anchoring theory specifies conditions for the occur-rence of biases due to the presence of anchor information in thejudgment context. These conditions are satisfied in Jasso’s vignettemethod. Predictably, results both from prior research and from ournew research indicated strong anchoring biases for both direct andindirect justice vignette measures.

5. The indirect method uses a statistical model whose specification dif-fers from the theoretical model that it ostensibly implements. Thisspecification error introduces biases of its own

Non-human primate neuroimaging is a rapidly growing area of research that promises to transform and scale translational and cross-species comparative neuroscience. Unfortunately, the technological and methodological advances of the past two decades have outpaced the accrual of data, which is particularly challenging given the relatively few centers that have the necessary facilities and capabilities. The PRIMatE Data Exchange (PRIME-DE) addresses this challenge by aggregating independently acquired non-human primate magnetic resonance imaging (MRI) datasets and openly sharing them via the International Neuroimaging Data-sharing Initiative (INDI). Here, we present the rationale, design, and procedures for the PRIME-DE consortium, as well as the initial release, consisting of 25 independent data collections aggregated across 22 sites (total = 217 non-human primates). We also outline the unique pitfalls and challenges that should be considered in the analysis of non-human primate MRI datasets, including providing automated quality assessment of the contributed datasets.

A large body of research has found an association between short birth intervals and the risk of infant mortality in developing countries, but recent work on other perinatal outcomes from highly developed countries has called these claims into question, arguing that previous studies have failed to adequately control for unobserved heterogeneity. Our study addresses this issue by estimating within-family models on a sample of 4.5 million births from 77 countries at various levels of development. We show that after unobserved maternal heterogeneity is controlled for, intervals shorter than 36 months substantially increase the probability of infant death. However, the importance of birth intervals as a determinant of infant mortality varies inversely with maternal education and the strength of the relationship varies regionally. Finally, we demonstrate that the mortality-reducing effects of longer birth intervals are strong at low levels of development but decline steadily toward zero at higher levels of development. These findings offer a clear way to reconcile previous research showing that birth intervals are important for perinatal outcomes in low-income countries but are much less consequential in high-income settings.

Since the publication of the primate brain volumetric dataset of Stephan and colleagues in the early 1980s, no major new comparative datasets covering multiple brain regions and a large number of primate species have become available. However, technological and other advances in the last two decades, particularly magnetic resonance imaging (MRI) and the creation of institutions devoted to the collection and preservation of rare brain specimens, provide opportunities to rectify this situation. Here, we present a new dataset including brain region volumetric measurements of 39 species, including 20 species not previously available in the literature, with measurements of 16 brain areas. These volumes were extracted from MRI of 46 brains of 38 species from the Netherlands Institute of Neuroscience Primate Brain Bank, scanned at high resolution with a 9.4-T scanner, plus a further 7 donated MRI of 4 primate species. Partial measurements were made on an additional 8 brains of 5 species. We make the dataset and MRI scans available online in the hope that they will be of value to researchers conducting comparative studies of primate evolution.

This paper analyzes the diffusion of contact-induced linguistic innovations in Portuguese spoken in Maputo, Mozambique, in two datasets from 1993/4 and 2007, focusing on quantitative accounts of linguistic innovations at lexical, lexico-syntactic, syntactic and morphosyntactic levels. Overall, innovative features that registered in the two datasets are qualitatively the same. Results confirm an increase in the frequency of innovative features related to second language acquisition and language contact at all linguist levels, with particularly high diffusion rates of morphological simplifications. This increase may be related to bilingualism and changes in use of, access to, and input of Portuguese. Furthermore, the qualitative stability of features may be a sign of an emerging usage norm.

We present formal evolutionary models for the origins and persistence of the practice of Female Genital Modification (FGMo). We then test the implications of these models using normative cross-cultural data on FGMo in Africa and Bayesian phylogenetic methods that explicitly model adaptive evolution. Empirical evidence provides some support for the findings of our evolutionary models that the de novo origins of the FGMo practice should be associated with social stratification, and that social stratification should place selective pressures on the adoption of FGMo; these results, however, are tempered by the finding that FGMo has arisen in many cultures that have no social stratification, and that forces operating orthogonally to stratification appear to play a more important role in the cross-cultural distribution of FGMo. To explain these cases, one must consider cultural evolutionary explanations in conjunction with behavioral ecological ones. We conclude with a discussion of the implications of our study for policies designed to end the practice of FGMo.

Using conscription data and follow ups from a large representative sample of Swedish men, and in accordance with earlier studies, we found a bell shaped association between male height and the hazard-for not being unmarried. The shape of this association was not affected by indicators of health and socioeconomic status and it might, instead, be due to microeconomic factors such as supply and market value. A negative linear association between male height and the hazard for divorce once married was also found, and this association was accounted for by indicators of socioeconomic status.

Liberals and conservatives often take opposing positions on moral issues. But what makes a moral position liberal or conservative? Why does public opinion tend to become more liberal over time? And why does public opinion change especially fast on certain issues, such as gay rights? We offer an explanation based on how different positions connect with different kinds of moral arguments. Based on a formal model of opinion dynamics, we predicted that positions better connected to harm and fairness arguments will be more popular among liberals and will become more popular over time among liberals and conservatives. Finally, the speed of this trend will be faster the better the position connects to harm and fairness arguments. These predictions all held with high accuracy in 44years of polling on moral opinions. The model explains the connection between ideology and moral opinions, and generates precise predictions for future opinion change.

What determines countries’ successful transition to democracy? This article explores the impact of granting civil rights in authoritarian regimes and especially the gendered aspect of this process. It argues that both men's and women's liberal rights are essential conditions for democratisation to take place: providing both women and men rights reduces an inequality that affects half of the population, thus increasing the costs of repression and enabling the formation of women's organising – historically important to spark protests in initial phases of democratisation. This argument is tested empirically using data that cover 173 countries over the years 1900–2012 and contain more nuanced measures than commonly used. Through novel sequence analysis methods, the results suggest that in order to gain electoral democracy a country first needs to furnish civil liberties to both women and men.

Primate brains differ in size and architecture. Hypotheses to explain this variation are numerous and many tests have been carried out. However, after body size has been accounted for there is little left to explain. The proposed explanatory variables for the residual variation are many and covary, both with each other and with body size. Further, the data sets used in analyses have been small, especially in light of the many proposed predictors. Here we report the complete list of models that results from exhaustively combining six commonly used predictors of brain and neocortex size. This provides an overview of how the output from standard statistical analyses changes when the inclusion of different predictors is altered. By using both the most commonly tested brain data set and the inclusion of new data we show that the choice of included variables fundamentally changes the conclusions as to what drives primate brain evolution. Our analyses thus reveal why studies have had troubles replicating earlier results and instead have come to such different conclusions. Although our results are somewhat disheartening, they highlight the importance of scientific rigor when trying to answer difficult questions. It is our position that there is currently no empirical justification to highlight any particular hypotheses, of those adaptive hypotheses we have examined here, as the main determinant of primate brain evolution.

91. A Comparison of Individual Learning and Social Learning in Zebra fish Through an Ethorobotics ApproachYang, Yanpeng

et al.

Clément, Romain J. G.

Ghirlanda, Stefano

Stockholm University, Faculty of Humanities, Department of Archaeology and Classical Studies, Centre for Cultural Evolution. Brooklyn College, United States; The Graduate Center of the City University of New York (CUNY), United States.

Social learning is ubiquitous across the animal kingdom, where animals learn from group members about predators, foraging strategies, and so on. Despite its prevalence and adaptive benefits, our understanding of social learning is far from complete. Here, we study observational learning in zebra fish, a popular animal model in neuroscience. Toward fine control of experimental variables and high consistency across trials, we developed a novel robotics-based experimental test paradigm, in which a robotic replica demonstrated to live subjects the correct door to join a group of conspecifics. We performed two experimental conditions. In the individual training condition, subjects learned the correct door without the replica. In the social training condition, subjects observed the replica approaching both the incorrect door, to no effect, and the correct door, which would open after spending enough time close to it. During these observations, subjects could not actively follow the replica. Zebra fish increased their preference for the correct door over the course of 20 training sessions, but we failed to identify evidence of social learning, whereby we did not register significant differences in performance between the individual and social training conditions. These results suggest that zebra fish may not be able to learn a route by observation, although more research comparing robots to live demonstrators is needed to substantiate this claim.